has the numbers 5500 - 42001 on the label

Also 16J003 and ZH01N on the bottom of the label

No idea of what machine or implement this is for  strimmer , hedge trimmer   (?)  as it came from a box of bits rescued from a skip outside a house who's previous tenant was a model aircraft enthusiast - he had some big models....................sadly he had passed away.

I would welcome some further information in the hope of being able  to sell these and other parts on..............